Spray gun



May 22, 1951 w. P. DALRYMPLE SPRAY GUN Filed April 10, 1948 Patented May 22, 1951 UNlTED STATES PATENT OFFHCE SPRAY GUN Application April 10, 1948, Serial No. 20,210

1 claim. 1

This invention relates to spray guns of the type utilized for spraying surface coating materials, and particularly the invention relates to spray guns for spraying emulsions of materials such as asphalt.

While spray guns have heretofore been pro vided for spraying emulsions, such guns were what may be termed special guns which were designed and manufactured differently than most conventional spray guns. Such guns were therefore relatively expensive. It is therefore an important object of the present invention to enable emulsion spray guns to be made in a large measure from standard parts that are used in the more widely used paint spray guns, and a related object is to enable this to be done in a simple and expeditious manner.

Other objects are to enable the emulsion control valve in such a gun to be operated by the usual material-control valve actuating structure of a paint spray gun; to enable an emulsion noz zle structure to be put in place in a simple manner on a gun body of the construction used for paint spray guns; and to simplify manufacture, upkeep and cleaning of such guns.

Other and further objects of the present invention will be apparent from the following description and claim and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment and the principles thereof and what I now consider to be the best mode in which I have contemplated applying those principles. Other embodiments of the invention embodying the same or equivalent principles rn-ay be used and structural changes may 'be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claim.

In the drawings:

Fig. l is a vertical sectional view taken through an emulsion spray gun embodying the features of the invention;

Fig. 2 is a front elevational view of the spray I head as viewed from the right in Fig. l; and

Fig. 3 is a vertical sectional view taken along the lire 3-3 of Fig. l.

For purposes of disclosure the invention has been illustrated in the drawings as embodied in a pistol-grip type of spray gun of the same general construction as the spray gun disclosed in my copending application Serial No. 734,819, filed March 14, 1947. This spray gun has a main body I with a downwardly extending handle II at what may be termed the rear end of this body. At the forward end of the body lll, an adapter fitting I2 is secured in place on the body Ill by means including a cap screw I3, and at the forward end of the fitting I2, a spray head I5 is secured in place by a threaded retaining collar lli. The emulsion material is conducted into the fitting I2 at the lower end thereof through a supply inlet pipe Il that defines a large area material passage IIM within the fitting I2. At its upper end the passage I'IM is in valvecontrolled communication lwith a horizontal passage IB formed in an internal nozzle member 20 that is threaded into the forward face of the fitting I2 so as to abut the forward face thereof, as will hereinafter be described in detail.

The flow of emulsion material through the nozzle I5 is controlled by a valve 28 which will hereinafter be described in detail, this valve being removably mounted on the forward end of a valve stem 29 that extends rearwardly and is adapted to be operated to open the valve 28 by a main control lever 3i? in the manner described inthe aforesaid copending application, and when the vaive 28 is opened, the emulsion material is withdrawn or aspirated through the nozzle I5 by the passage of pressure air through the nozzle id as will hereinafter be described. Such pressure air is supplied through a passage 32 formed in the handle II as described in the aforesaid copending application, and a main valve 3@ is arranged to control such air passage and is in turn controlled by the main control lever 39. The air which passes the main valve 34 passes into another passage 33 in the handle II and is discharged upwardly through an adjustable sleeve valve 35 and into a horizontal passage 36 that `extends forwardly in the body I so as to open through a forward face IBF on the body Il! and into the fitting I2, as will be described.

As pointed out hereinbefore, the primary structural elements oi the emulsion gun of the present invention are of the same form and structure used in producing spray guns for handling paint and like materials, and in this regard it will be noted that the main body I has a mounting lug 38 projecting downwardly therefrom and at the forward end thereof so that the forward face of the lug 38 constitutes a downward continuation of the surface ISF. The lug 38 constitutes a part of the means for mounting the adapter fitting I2, and a horizontal bore 39 is formed therein in alignment with a valve operating sleeve 4!) that is mounted within and ward end, and a spring 4I is disposed in the sleeve 40 for affording a yielding connection between the sleeve elli and a valve stem element such as the stem 29, as Set forth in such copending application.

The fitting I2 is provided with a rear surface IER. which is disposed against the front facev 4QF of the body Iii, and at its upper end the iitting I2 has a flange I2T through which the securing screw i3 is extended into the body it above the passage 36. The tting l2 has a mounting nipple 42 extended rearwardly through the opening 39 in the lug 38, and rearwardly of the lug 38 a fastening nut 43 is threaded onto the nipple 432. The nipple 4? has a bore it formed axially thereof through which the seem 29 slidably extends, and a packing recess is formed in the rear end of the nipple within which a packing 45 and a spring i8 are disposed, and the spring is compressed by a packing nut il threaded onto the rear end of the nipple t2. At its rear end the stem 2e has a head ZH formed thereon which is disposed within the sleeve #Bil and is held against the flange l? by the spring 4I.

At its forward end the fitting I2 has an extension IZE that is concentric with the bore it and this extension iZE terminates in a forward face IZF that is parallel to the face 52B. A threaded bore 5G is formed rearwardly through the face 12F so as to be concentric with the bore 4d, and this bore El] opens into the upper end of the inlet passage IiM. The forward end of the threaded bore hl is tapered as at 5&3'1 to afford a seat for a rearwardly tapered head ZH that is formed on the inner nozzle 20. The inner nozzle 2d is generally sleeve-like in form so that rearwardly of the head dT, the nozzle 29 has a threaded nipple ZEN which is threaded rearwardly into the bore E@ so as to seat complemental tapered surfaces of the head 2ST in the tapered seat 55T, and when this relation is reached, the rear end of the nipple ZN is disposed in an exposed or slightly extended relation within the upper end of the material passage I lM. The rear end of the nipple 23N has a tapered concentric seat S formed therein against which the valve member 2S may be seated. As will be evident in Fig. l, the valve member 28 is generally ball-like in form and is made from a resilient material such as rubber. axially of the valve 28, a mounting sleeve Edit/I is extended through the valve in an interlocked relation, a screw head 28H being formed in an exposed relation on the forward end of the sleeve ZSM, and the sleeve 28M has a threaded axial bore extended into the rear end thereof so that the sleeve 28M may be threaded onto the threaded forward end of the stem 29.

Forwardly of the head 26H, the nozzle 2S is tapered inwardly as at 2ST, so as to terminate in a reduced forward end which deines a reduced internal material discharge orifice I iiD, and the head Ztl-l and the tapered portion 23T are surrounded in spaced relation by the out r cap [5C of the nozzle structure i5. The cap C has a cylindrical rear portion IER which extends into an annular groove IZG formed in the forward face IZF of the fitting concentric with the bore 52, and an outwardly extending annular flange ISF on the cylindrical portion ISR fits against the face IEF so as to define the relative location of the cap IBC on the fitting I2. The collar I is flanged over the forward face of the flange IEF and is threaded onto the forward portion of the extension IEE. Forwardly of the cylindrical porti-on 55B, the cap 55C is tapered inwardly as at iT so as to terminate in a tapered discharge nose 5N that is aligned with the inner discharge orifice IED. The discharge nose iN is spaced outwardly at its rear end from the forward end portion of the inner discharge passage iD, and extends forwardly so that material drawn :from the passage SSD be mixed with the asperating air while the air and the material move forwardry through the discharge nose IN.

It will be noted that the rear end of the cylindrical portion fills but a small portion of the cross sectional area of the groove i213 which therefore has sufficient effective area to serve as a distributing passage for pressure air received from the main air passage of the body it. Thus the fitting I2 has a pair of parallel bores 55 extended rearwardly from the upper portion of the groove E2G and positioned so that the rear ends of such bores E5 open through the face 2R and into the bore In this connection it should be noted that the passage or bore 35 normally serves both as an air passage and as a mounting space for supplemental valve means for governing or adjusting the action of the wing jets in conventional paint spray guns, as described in my aforesaid co-pending application. In producing an emulsion gun under the present invention, such supplemental valve means are not required and the rear end of the passage is therefore closed by a plug From the foregoing description it will be evident that the present invention materially simplifies and reduces the cost of producing emulsion spray guns; and that such emulsion guns as produced under this invention are simple in character and may be easily cleaned and kept in repair by the user.

Thus while I have illustrated and described the preferred embodiment of my invention, it is to be understood that this is capable of variation and modification and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claim.

I claim:

An emulsion spray head adapted for use with a spray gun body having a main control rnenber, a main air valve in the gun body actuated by the control member, the gun body having an air passage therethrough, a mounting face on the gun body, the spray head having a ccmplemental mounting face on one end adapted to be secured to the mounting face of the gun body, a nozzle receiving means on an opposite face of the spray head and a material inlet passage through the spray head extending downwardly therefrom between the two faces, the spray head having an air passage therein above the material passage and communicating with the main air passage of the gun, an air receiving and distributing circumferential groove in the nozzle receiving face in communication with and receiving air from the air passage in the spray head and adapted to distribute the air, an outer nozzle secured to the nozzle receiving face and having a rearwardly extending cylindrical portion spaced inwardly from an outer cylindrical wall thereof and forming a cylindrical shoulder on the nozzle adjacent lthe cylindrical portion, the cylindrical portion being of less cross sectional thickness than the width of the groove and of less length than the depth of the groove when positioned therein, the cylindrical portion thereby serving to center the outer nozzle, the cylindrical shoulder abutting that part of the nozzle receiving face of the spray head outwardly of and surrounding the receiving and distributing groove, the outer nozzle having an interior cylindrical portion in communication with the circumferential receiving and distributing groove, an inner nozzle disposed within the outer nozzle and having a cylindrical portion thereof concentrically within and spaced from the cylindrical portion of the outer nozzle and forming therewith a cylindrical air receiving distributing passageway that is in direct communication with the circumferential groove, a mounting nipple engaging the nozzle receiving face of the spray head and extending laterally into the material inlet passage and providing a valve seat on the inner end thereof, a valve member comprising a valve rod slidably mounted in said head and movable by said main control member, a v-valve mounting 6 sleeve threadably mounted on the valve rod, a resilient ball-like valve member secured to said mounting sleeve and cooperating,v with said valve seat to prevent material ow from said material passage into the inner nozzle. f WlLLIAM P. DALRYMPLE.

REFERENCES CITED The following references are of record in the 

